Hey so I usually use Mobil 1 5-30 I’ve always used that in all my cars and the 2011 wrx is no different. However I’m learning now that it’s not a good oil to use with our cars. Everybody has said to use rotella t6 5-40 but I saw a post that said they changed the formula for the t6 and it’s no longer good for our cars. As of right now what’s the best oil for a 2011 stock wrx. I also use the stock oem subie filter.